I'll try to keep this long story short. A couple of days ago my iPhone 4 (GSM model, I personally bought it from Apple Store fully unlocked) lost reception and instead of carrier's name it just said "No Service". Something similar happened a week or two ago - it said "No Service" but somehow fixed itself. This time it did not - I was out all night and the battery had drained. When I turned it on again it just said "No Service" and stayed that way for many hours. I've tried resetting network settings, all settings and eventually restore/update functions which eventually got me this far - I cannot bypass the activation screen and iPhone does not detect the sim card at all. It either states that it's "searching" or "no sim". Telephone was on iOS 5.0.1 and jailbroken and after all the restore/update nonsense it's on iOS6. I have already tried jailbreaking it again, but gained nothing. iPhone still cannot detect the sim card (on the activation it says "Please insert a sim card") so it is pretty much useless. Oh, and phone was really cared for - nor was it dropped many times, nor it had any technical problems before. So the question is - what happpened and is it fixable? Thanks in advance!

As far as I know, activation requires a sim from a carrier which actually offers iPhones. You can't activate with a TMO sim because they aren't an official carrier (in the US anyway). Pop in an ATT sim, this will activate it. From then on, you can use any other sim.

hey I have been reading all your comments . . .ill just insert mine since it would be a quick question . . lets say I have an AT&T locked (which is actually softbank locked lets just assume it is AT&T) will any sim would do as long as it is AT&T?

Would this work even if I am not in the network coverage of AT&T? I know you said that it doesn't have to be an active SIM (thus implying that it doesn't need to be in the network coverage of AT&T) but I read on the apple community support forums that when this occurs, the phone becomes unusable with even AT&T and is "bricked" (as well as some snide remarks about how jail-breaking is not as safe as is claimed, etc).

Is there any other option for someone who had a jail-broken iPhone 3GS (was jailbroken out of necessity as I had to move to another country and as the period of my stay was not predetermined, the roaming charges had I stayed on AT&T would have been extreme) and updated to iOS6 during a restore (phone was getting stuck on the loading screen after upgrading one of the installed cydia apps (either the SIM unlocker or AppSync, can't be sure).

@reV17 He did say it came from Apple Store fully unlocked so inserting a sim from any carrier will properly activate it, not just an AT&T sim in particular. He can't be hacktivated since there is no tool to hacktivate iOS6 at the moment.

can it be a technical issue? or should I wait for a proper jailbreak to come out and try to hacktivate the phone and then change the basebands etc? I was planning to keep the phone unjailbroken, but now.. And yes, it was factory unlocked with no hactivations or anything before this happened.